Xcode Interface Builder未显示App Delegate对象

Question

我正在通过“IOS编程：大书呆子牧场指南（第2版）”教自己Objective-C和iOS编程，我遇到了一个问题，教程要求我创建与App Delegate对象的连接，但是这个对象没有出现在“接口”构建器的“对象”列表中。对于我来说，我很确定它可能是一个拼写错误，也可能是版本不同，因为本书稍微落后于我的Xcode版本（4.2）。我已经包含了代码。我很公平确定MOCAppDelegate对象应该出现在IB中，但我还不熟悉，知道我需要做什么代码更改。特定问题：如何调整下面的代码以便我得到一个对象IB中的对象列表，以便我可以按照教程图形中的说明执行连接？

注意：我研究并发现了这个：Having trouble hooking up instance variables to AppDelegate但是这个解决方案对我不起作用（或者我没有正确实现）

头文件

#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
#import <MapKit/MapKit.h>

@interface MOCAppDelegate : UIResponder <UIApplicationDelegate, CLLocationManagerDelegate>
{
    CLLocationManager *locationManager;

    IBOutlet MKMapView *worldView;
    IBOutlet UIActivityIndicatorView *activityIndicator;
    IBOutlet UITextField *locationTitleField;
}

@property (strong, nonatomic) IBOutlet UIWindow *window;


@end

实施档案

#import "MOCAppDelegate.h"

@implementation MOCAppDelegate

@synthesize window = _window;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    //Create location manager object
    locationManager = [[CLLocationManager alloc] init];
    [locationManager setDelegate:self];

    //We want all results from the location manager
    [locationManager setDistanceFilter:kCLDistanceFilterNone];

    //And we want it to be as accurate as possible
    //regardless of how much time/power it takes
    [locationManager setDesiredAccuracy:kCLLocationAccuracyBest];

    //Tell our location manager to start looking for it location immediately
    [locationManager startUpdatingLocation];

    //We also want to know our heading
    if (locationManager.headingAvailable == true) {
        [locationManager startUpdatingHeading];
    }


    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor darkGrayColor];
    [self.window makeKeyAndVisible];
    return YES;
}

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation
{
    NSLog(@"%@", newLocation);
}

- (void)locationManager:(CLLocationManager *)manager
       didUpdateHeading:(CLHeading *)newHeading
{
    NSLog(@"%@", newHeading);
}

- (void)locationManager:(CLLocationManager *)manager
       didFailWithError:(NSError *)error
{
    NSLog(@"Could not find location: %@", error);
}

- (void)dealloc
{
    if( [locationManager delegate] == self)
        [locationManager setDelegate:nil];
}

- (void)applicationWillResignActive:(UIApplication *)application
{
    /*
     Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
     Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
     */
}

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    /*
     Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later. 
     If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
     */
}

- (void)applicationWillEnterForeground:(UIApplication *)application
{
    /*
     Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
     */
}

- (void)applicationDidBecomeActive:(UIApplication *)application
{
    /*
     Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
     */
}

- (void)applicationWillTerminate:(UIApplication *)application
{
    /*
     Called when the application is about to terminate.
     Save data if appropriate.
     See also applicationDidEnterBackground:.
     */
}

@end

Answer 1

将NSObject的一个实例拖到你的.xib中，然后将其放入Objects部分，就像你所获得的指令一样。然后选择它并在身份检查器（在右侧，它显示“自定义类”）中将其类型更改为“MOCAppDelegate”（或您喜欢的任何类）。

Answer 2

您应该将“NSObject”从对象库拖到您要连接的视图控制器下方黑色条上的故事板上。然后，单击NSObject并在身份检查器中将类更改为AppDelegate。然后，您可以创建与AppDelegate的连接。

Answer 3

MOCAppDelegate = AppDelegate

您在为项目命名时为您生成了代码。 UIApplication对象的委托通常根据项目名称略有不同。

（毫无疑问，任何印刷版书籍都使用较旧的Xcode。）

选择Files Owner和Identity Inspector（命令-alt-2）以确认文件所有者是应用代表的占位符。